Weed-burning device



H. E. WOOLERY IBBD BURNING DEVICE 2 Sheets-Sheet 1 mad- D60. 27. 1924 7/ In /en for:

1'7. E. Woo/erg By M1 W Patented July 19, 1927.

HORACE nl'woonnnr, ors'r; PAUL, mmimso'm, assrolion r0 WQOIERY mom-1m COMPANY, OF MINNEAPOLIS, MINNESOTA.

' WEED-BURNING 1mm Application filed. December 27, 1324.. semi m. mam,

My invention relates to wood burning devices and particularly to such devices mount ed on a wheeled frame which can be; propolled along railway tracks. It will be obvious, however, that the wheeled frame might be propelled directly over the ground without being run on rails. An object is to pronide a device of this.v character which embodies a hood consisting of a metal shell linede with refractory material to; protect, the metal from the intense heat generated. within the hood. Another, object. is to provide a device of this character-in; which a hoodis supplied withv a blast of air which during its passage picksup-liquid fuel and thoroughly uaporizes it before it. is. delivered to the hood. Anotherobi ect is to increase the efficiency of the device by providing Venturi, tubes through which the blast of air passes.

The full objects and advantagesof my in vention will appear in connection with the detailed description thereof and the novelv features embodied in my inventive idea will be particularly pointed out in the claims.

In the accompanying drawings which illustrate a practical, embodiment of my invention, Fig. 1 is a side-elevational view of the device. Fig. 2 is a sectional detail view of the fuel feeding part of the device. Fig. 3 is. a view of the 'device, in longitudinal vertical section. 7

Referring to the construction shown in the drawings, the device includes a frame mounted on a pair of front wheels 10 and a pair of rear wheels 12 adapted to run on rails of a railway track. The frame consists of a pair of bars 14 supported by the front wheels and a pair of bars 16 supported by the rear wheels, these bars extending up convergently and their upper ends being connected by a pair of horizontal, longitudinal beams 18, tied together by transverse rods 20. Secured to the beams 18 are two pairs of internally threaded collars 22 through which pass vertical screw rods 24 to whose upper ends handwheels 26 are secured. The lower ends of these screw rods are rotatively attached to angle pieces 28 which are secured to a downwardly flaring hood, having an open bottom. This hood consists of a metal shell 30 whose rear side is reinforced by ribs 32. The interior ofthe metal shell is lined with a refractory lining which may consist of fire bricks 34 secured to the shell in any has an opening around which is secureda forwardly extending tubular member 36;

withinwhich a. mixing. chamber 31. A blower 38 in the embodiment shown, is

mounted on a separate car 402. The delivery tube 42 ofthe blower: extends rearwardly and at its rear end attached to a Venturi tube 44 having a constricted portion 46.. The rear end of the .Venturi tube 44 is in substantiallythe Same vertical plane as the front end of the. tubular nmmber 36 but is considerably smaller and concentrically disposed so that air may be drawninto the: member 36 from around the tube: 44. Lo rated within the Venturi tube 44 is a. second and smaller Vcnturi tubev 481 having a con-- stricted portion 50 lying in the same verti cal planeas the constricted portion 46. The; tube 45$ is carriedv by the, upper: end of a tubular member- 52 which passes through the lower side: of. the tube 44 as best shown in Fig. 3 and as. shown may be held. in place is screw threaded. engagement with the wall.

epassageway from the member 52into the tube; 48 is contracted, to provide a conical valve seat 54 for co-operation with a needle valve fiti carried by-a stem 58, screw threaded through the lower end of theemember 52% that. the passageway into the'tube 48 may be regulated with rest precision. A. pipe 60. leads through t e side of the member 52 for supplying liquid fuel from any conveniently positioned tank.

The operation and advantages of my invention will now be understood. The cars carrying the hood and the blower may be propelled along the track by any suitable source of power. The blast of air delivered by the blower passes through the Venturi tube 44 and into the mixing chamber 37. A portion of'this air passes through the smaller enturi tube 48 and produces a suction which draws liquid fuel up from the tubular member 52 so that this fuel is delivered into the mixing chamber 37. Additional air is drawn into the mixing chamber through the annular space around the tube 44, and the liquid fuel is thoroughly mixed with air and is vaporized before it passes into the hood where it burns. The bottom of the hood is spaced only a short distance above the ground so that the intense heat generated in the hood causes Weeds and grass over which the hood passes to burn very quickly. The hood is suitable manner. The front side of the hood positioned forwardly upon its supporting ward movement of the car, the flame flows backwardly and the forward placing of the hood prevents the heat from having an in jurious effect on the rear wheels and supporting structure. The interior of the hood is subjected to such intense heat that the metal shell is apt to become buckled and soon destroyed unless some means is adopted to prevent this. Heretofore water has been placed on the outside of the hood but such method does notkeep the flame from contact with the inside surface of the metal shell. Furthermore, the intenseheat drives off the water in the form of steam with resultant waste of heat and it also requires time and labor to replace the water. These defects are overcome by providing the metal shell with a refractory lining such as fire brick. In the operation of the device the effect of the air blast from the blower is increased by the provision of the two Venturi tubes one inside of the other and having their constricted portions lying in a common plane. This causes an adequate supply of iquid fuel to be drawn up from the tube 52 in amount which can be regulated with great nicety by turning the needle valve. Thorough mixing of the air with liquid fuel occurs in the mixing chamber 37 and intense heat is produced within the hood with a relatively small amount of fuel. The distance of the hood from the ground may be readily varied by turning the hand wheels 26.

I claim:

1. A weed burning device comprising a Wheeled frame, a metal shell constituting a hood supported from said frame and having an open bottom in proximity to the ground, a refractory lining for the top and sides of said metal shell extending to the bottom of the latter, the front wall of said hood having a single large opening thru the metal and refractory lining, a tubular member connected with said opening, said tubular member constituting a mixing chamber, a blower, a delivery tube extending from said blower for delivering a blast of air into said mixing chamber, and a supply pipe for delivering liquid fuel into position to be picked up by said blast of air.

2. A weed-burning device comprising a wheeled frame, a hood supported from said frame and having an open bottom in proximity to the ground, a tubular member leading into said hood and extending forwardly therefrom, said tubular member constituting a mixing chamber, a blower, a delivery tube extending from said blower for delivering a blast of air into said mixing chamber, a Venturi tube positioned concentrically within said delivery tube, and means for supplying liquid fuel to said Venturi tube.

3. A weed burning device comprising a wheeled frame, a hood supported from the forward portion of said frame so as to be disposed considerably in advance of the rear portion of the frame, said hood having an open bottom in proximity to the ground, a tubular member extending forwardly from said hood and constitutinga mixing cham ber, means for producing a combustible gaseous mixture of air and liquid fuel in said mixing chamber, and a blower for forcing said gaseous mixture into said hood.

In testimony whereof I hereunto aifix my signature.

HORACE E. WOOLERY. 

